Narrative:

On a regular overnight layover inspection, found hydraulics misting in the left wheel well. Found 2 hydraulic lines rubbing together. A 1/2 inch #8 line and a 1/4 inch #4 line. The defective area of tubing was cut out and new tubing was formed and double spliced in using splices. This was necessary because damage was in a bend area. The #4 line was idented as going to the aileron 'a' modular package and going to some type of spoiler mixer assembly. The #8 line was going from the forward bulkhead disconnect then through the keel beam area and to the right wheel well. Did not identify where. After repairs were made, accumulator head pressure was svced and hydraulics leaked checked. Flaps were in the down position so we raised flaps and while traveling up, spoilers and ailerons were exercised. Operations and leaks check good. Hydraulic quantity gauge read 4.5 units before repairs and after repairs and chkout gauge read 4 units. No hydraulics servicing required. Aircraft took off and upon gear retraction hydraulic quantity dropped down to 2.5 units. Pilot commanded aircraft back to base for loss of hydraulics or low quantity on gauge. Upon landing, hydraulics were svced to 4.4 units and no leaks found. Aircraft departed. No discrepancies since.

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Original NASA ASRS Text

Title: A B727-200 RETURNED TO THE FIELD DUE TO HYD QUANTITY DROPPING FROM 4 PT 4 GALS TO 2 PT 5 GALS DUE TO INCORRECT REPAIR PROCS.

Narrative: ON A REGULAR OVERNIGHT LAYOVER INSPECTION, FOUND HYDS MISTING IN THE L WHEEL WELL. FOUND 2 HYD LINES RUBBING TOGETHER. A 1/2 INCH #8 LINE AND A 1/4 INCH #4 LINE. THE DEFECTIVE AREA OF TUBING WAS CUT OUT AND NEW TUBING WAS FORMED AND DOUBLE SPLICED IN USING SPLICES. THIS WAS NECESSARY BECAUSE DAMAGE WAS IN A BEND AREA. THE #4 LINE WAS IDENTED AS GOING TO THE AILERON 'A' MODULAR PACKAGE AND GOING TO SOME TYPE OF SPOILER MIXER ASSEMBLY. THE #8 LINE WAS GOING FROM THE FORWARD BULKHEAD DISCONNECT THEN THROUGH THE KEEL BEAM AREA AND TO THE R WHEEL WELL. DID NOT IDENT WHERE. AFTER REPAIRS WERE MADE, ACCUMULATOR HEAD PRESSURE WAS SVCED AND HYDS LEAKED CHKED. FLAPS WERE IN THE DOWN POS SO WE RAISED FLAPS AND WHILE TRAVELING UP, SPOILERS AND AILERONS WERE EXERCISED. OPS AND LEAKS CHK GOOD. HYD QUANTITY GAUGE READ 4.5 UNITS BEFORE REPAIRS AND AFTER REPAIRS AND CHKOUT GAUGE READ 4 UNITS. NO HYDS SVCING REQUIRED. ACFT TOOK OFF AND UPON GEAR RETRACTION HYD QUANTITY DROPPED DOWN TO 2.5 UNITS. PLT COMMANDED ACFT BACK TO BASE FOR LOSS OF HYDS OR LOW QUANTITY ON GAUGE. UPON LNDG, HYDS WERE SVCED TO 4.4 UNITS AND NO LEAKS FOUND. ACFT DEPARTED. NO DISCREPANCIES SINCE.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.